Moisture Content Experiment

ensure 09-02-2013 Experiment 1(a) Laboratory determination of weewee ( dampure) theme of a country sample by oven drying method Reference ASTM D2216-98 Need and scope of the experimentation In almost all country adjudicates indwelling wet subject matter of the alter is to be rigd. The knowledge of the natural wet field is inhering in all studies of stigma mechanics. To sight a few, natural moisture content is social occasiond in determining the bearing tipacity and settlement. The natural moisture content depart give an idea of the state of soil in the field.Apparatus 1. Containers (Tin or Aluminum) with lids. 2. Balance, sensitive to 0. 01gm 3. Oven with accurate temperature control at one hundred ten + 5oC (230 + 9oF) Discussion 1. moisture Content (w) It is defined as the ratio of the cud of the pore or tolerant piddle in a disposed(p) push-down storage of material to the jam of the solid material. w=MwMs? nose candy Mw = hole of water in grams Ms = Ma ss of solid particles in grams (i. e. oven desiccate measuret of soil) 2. Representative quantity of Test SpecimenThe minimum mass of moist material selected to be exemplification of the total sample shall be in accordance with the following Maximum particle size ( vitamin C% passing) ideal Sieve Size Recommended minimum mass of moist test model for water content reported to 0. 1% Recommended minimum mass of moist test specimen for water content reported to 1% 2 mm or less No. 10 20 g 20 g 4. 75 mm No. 4 vitamin C g 20 g 9. 5 mm 3/8-in. calciferol g 50 g 19. 0 mm ? -in. 2. 5 kg 250 g 37. 5 mm 1? -in. 10 kg 1 kg 75. 0 mm 3-in. 50 kg 5 kgNOTE-1If it is suspected that gypsum is present in the soil, the soil sample should non be subjected to a temperature beyond 80oC. Otherwise gypsum would lose its water of crystallization, thereby touching the results of moisture content. Oven drying at 80oC may, however, be continued for a longer term in order to ensure complete evaporat ion of free water present in the sample. NOTE-2To assist the oven drying of large test samples, it is advisable to use containers having large surface area and break up the material into littler aggregations.NOTE-3Since several(prenominal) dry materials may absorb moisture from moist specimens the dried specimens should be removed before placing new roiled soil samples in the oven. Procedure 1. Take sufficient number. of avoid, clean containers and mark them (if they are not marked) with an identifying number or code. 2. Weigh the container and record the weight as M1 to the hot 0. 01gm. 3. Take representative sample from different depths (0. 25, 0. 5, 0. 75m) from the field. 4. Quickly institutionalize the representative sample of the wet soil in the container. . Immediately weigh the container with the wet soil sample to the nearest 0. 01 gm. Record the weight as M2. In case it is not feasible to determine the weight immediately, cover the container with a lid. 6. Place the c ontainer with the soil sample in the drying oven at constant temperature of cx+5oC for 24 hours (till constant weight is achieved). 7. After 24 hours remove the container from oven and weigh to the nearest 0. 01 gm. Record the weight as M3. Calculations Mass of empty container = M1=4. 71(g)Mass of empty container + wet soil = M2= 43. 88(g) Mass of container + dry soil = M3=37. 41(g) Mass of water = Mw = M2 M3 = 6. 47(g) Mass of soil solids = Ms = M3 M1 = 33. 24(g) Moisture Content = w=MwMs? 100=M2-M3M3-M1? 100 body politic Moisture Content Determination 1 abstrusity ( ) 2 Soil Description 3 Container No. 143 4 Mass of empty container (M1), g 4. 71 5 Mass of Container + Wet Soil (M2), g 43. 88 6 Mass of Container + dry Soil (M3), g 37. 41 7 Moisture Content w = (M2 M3)/(M3 M1) % 19. 46 % Comments ) Oven drying is a time taking process and not much accurate as rapid moisture cadence. 2) It needs caring for long time in order to get the good results. 3) It needs attentions i n case if some other material like Gypsum is present in the soil. In such cases temp. should have to be controlled otherwise the material may react and unfounded its water of crystallization which effects the results. 4) Above value of moisture content lies in Normal moisture content range. 5) Date 09-02-2013 Experiment 1(b) To determine moisture content of a soil sample by speedy moisture meter.Apparatus 1. speedy moisture meter (also called calcium carbide mechanical press moisture quizzer) 2. Built-in scale for weighing 3. Two 1. 25 inches (3. 175 cm) stigma balls 4. Cleaning brush and cloth 5. Scoop for measuring calcium carbide reagent 6. atomic number 20 carbide reagent Introduction The calcium carbide assail moisture tester provides a apace and simple means of determining moisture content of soil. It is particularly effectual for field determinations of moisture content in conjunction with field infatuation testing.The basic premise of the calcium carbide gas moist ure tester is that the free moisture in the soil reacts with calcium carbide reagent to form a gas called acetylene gas. CaC2+H2OCaO+C2H2 The acetylene gas pressure developed within the tester is displayed on the pressure dial gauge, which is calibrated to read directly moisture content (in %) by wet mass of soil. Since moisture content by definition is expressed as a percentage of dry mass of soil, the class periods obtained by speedy moisture meter are corrected employ the following expression w=wsp1-wsp? 00 Where w = moisture content in %. wsp= moisture content as obtained by speedy moisture meter expressed as decimal fraction Procedure 1. Weigh a 26 gram soil sample on the tarred scale and place it in the chapiter of the tester. 2. Place three scoops (approximately 24 gm) of calcium carbide and devil 1. 25 in (3. 175cm) steel balls in the larger chamber of the moisture tester. 3. With the pressure vessel in an approximately horizontal position, insert cap in the pressure ves sel and shut it by tightening the clamp.Take kick that no carbide comes in contact with the soil until a complete seal is achieved. 4. Raise the moisture tester to a vertical position so that the soil in the cap will fall into the pressure vessel. 5. commove the performer vigorously so that all soil lumps are gloomy to permit the calcium carbide to react with all available free moisture. The instrument should be shaken with a rotating motion so that the steel balls will not damage the instrument or cause soil particles to function embedded in the orifice leading to pressure diaphragm. 6.When the needle bread moving, read the dial while holding the instrument in a horizontal position at eye level. 7. Record the dial reading. 8. With the cap of the instrument pointed away from the operator, slowly release the gas pressure. Empty the pressure vessel and examine the material for lumps. If the sample is not completely pulverized, the test should be repeated using a new sample. 9. T he dial reading is the percent of moisture by wet mass and must be converted to dry mass. Note If the moisture content of the sample exceeds the narrow down of the pressure gauge 20 percent moisture), use half of the soil mass and double the dial reading. Other methods of determining moisture content quickly Other methods of measuring moisture content quickly intromit measurements by stove method and by micro wave oven methods. ASTM D4959-07 is apply for measuring by stove method and ASTM D4643-08 is used to measure moisture my micro wave method. Results and Comments Zero Error of Dial dullard = 0. 8 Dial Gauge Reading = 17. 6 Corrected Dial Gauge Reading = 16. 8 Wsp = 0. 68 W (Moisture Content) = 20. 19 % * Speedy Moisture meter give better and faster result than the ordinary oven drying. * In this method the water present in soil reacts with calcium carbide and results in acetylene gas which in turn gives the value of moisture content. * Speedy moisture meter method is an effi cient method as it doesnt involve too much time for its performance. It is used when tests are performed in the field. * Moisture content effects the soil resistivity, soil compaction and soil shear strength.